Packaging method of long-distance sensor

ABSTRACT

A package structure of a long-distance sensor includes a substrate, a light-emitting chip, a sensing chip, two packaging gel bodies, and a cap. The substrate has a bearing surface. The light-emitting chip and the sensing chip are disposed on the bearing surface and separated from each other. The two packaging gel bodies cover the light-emitting chip and the sensing chip respectively and are separated from each other. The cap is disposed on the bearing surface and the packaging gel bodies, fastened to the bearing surface and the packaging gel bodies by adhesive, and provided with a light-emitting hole located above the light-emitting chip and a light-receiving hole located above the sensing chip.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention relates generally to package structures and moreparticularly, to a package structure of a long-distance sensor and apackaging method of the same.

2. Description of the Related Art

The conventional package structure of the long-distance sensor ismanufactured in a way that a light-emitting chip and a sensing chip aredisposed on a substrate; then two packaging gel bodies are provided bymolding to cover the light-emitting chip and the sensing chiprespectively, and meanwhile each of the packaging gel bodies is providedon the top surface thereof with a hemispheric lens portion correspondingto the light-emitting chip and the sensing chip; at last, a cap isprovided by molding to be located above the substrate and the packaginggel bodies, so that the whole packaging process is accomplished. Itshould be mentioned that the cap is usually provided with alight-emitting hole and a light-receiving hole for accommodating thelens portions respectively.

However, in such manner that the packaging gel bodies and the cap areformed by two times of molding, the cap is not connected with thepackaging gel bodies and the substrate firmly. Besides, in such mannerthat the cap is formed by molding, the mold for molding can't bedisposed near the lens portions, so the cap can't be located near thelens portions, causing the long-distance sensor a relatively shortersensing distance. Therefore, the conventional package structure of thelong-distance sensor and the packaging method thereof still havedrawbacks and therefore need improvements.

SUMMARY OF THE INVENTION

Summarizing the above description, it is a primary objective of thepresent invention to provide a package structure of a long-distancesensor, which has the advantages that the packaging materials areconnected relatively more firmly and the sensing distance is relativelylonger.

The package structure of the long-distance sensor includes a substrate,a light-emitting chip, a sensing chip, two packaging gel bodies, and acap. The substrate has a bearing surface. The light-emitting chip andthe sensing chip are disposed on the bearing surface and separated fromeach other. The two packaging gel bodies cover the light-emitting chipand the sensing chip respectively and are separated from each other. Thecap is disposed on the bearing surface and the packaging gel bodies,fastened to the bearing surface and the packaging gel bodies byadhesive, and provided with a light-emitting hole located above thelight-emitting chip and a light-receiving hole located above the sensingchip.

As a result, the cap is fastened to the bearing surface and thepackaging gel bodies by the adhesive, so that the connection between thematerials of the package structure is improved.

It is another objective of the present invention to provide a packagingmethod of a long-distance sensor. The packaging method includes thesteps of:

(a) providing a substrate and disposing a light-emitting chip and asensing chip on a bearing surface of the substrate in a way that thelight-emitting chip and the sensing chip are separated from each other;

(b) covering the light-emitting chip and the sensing chip by twopackaging gel bodies respectively and separating the packaging gelbodies from each other; and

(c) disposing a preformed cap on the bearing surface of the substrateand the packaging gel bodies and fastening the cap to the bearingsurface of the substrate and the packaging gel bodies by adhesive.

Preferably, in the step (b) the two packaging gel bodies are formed bymolding to cover the light-emitting chip and the sensing chiprespectively.

As a result, because the cap is preformed, it can be directly glued bythe adhesive to be fastened to the packaging gel bodies and the bearingsurface. Besides, the packaging gel bodies and the cap are not formed bytwo times of molding respectively, so the drawback of the prior art thatthe cap can't be located near the packaging gel bodies and therefore thesensing distance is lowered can be overcome.

The detailed structure and features of the present invention will bespecified in the detailed description of the embodiments givenhereinafter. However, those skilled in the art should understand thatthe detailed description and the specific embodiments instanced for theimplementing of the invention are given for illustration only, not forlimiting the scope of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a top view of a first preferred embodiment of the presentinvention.

FIG. 2 is a sectional view taken along the line 2-2 in FIG. 1.

FIG. 3 is a sectional view of a second preferred embodiment of thepresent invention.

FIGS. 4A-4D are sectional views showing the manufacturing process of thefirst preferred embodiment of the present invention.

FIGS. 5A-5E are sectional views showing the manufacturing process of thesecond preferred embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIGS. 1-2, wherein a package structure 10 of along-distance sensor according to a first preferred embodiment of thepresent invention is shown, the package structure 10 includes asubstrate 20, a light-emitting chip 30, a sensing chip 40, two packaginggel bodies 50, and a cap 60.

The substrate 20 in this preferred embodiment may, but unlimited to, bea printed circuit board (usually referred to as “PCB”), abismaleimide-triazine (usually referred to as “BT”) substrate, a glassfiber substrate (usually referred to as “FR4”), or a direct bondedcopper (usually referred to as “DBC”) substrate. In this way, themanufacturing cost of the substrate 20 is relatively lower. Thesubstrate 20 has a bearing surface 22.

The light-emitting chip 30 is disposed on the bearing surface 22, andmay be electrically connected with the substrate 20 by wire bonding. Inthis preferred embodiment, the light-emitting chip 30 is an LED chip foremitting a light source.

The sensing chip 40 is disposed on the bearing surface 22 and separatedfrom the light-emitting chip 30. The sensing chip 40 may be alsoelectrically connected with the substrate 20 by wire bonding. Thesensing chip 40 is used for sensing the light source emitted by thelight-emitting chip 30.

The two packaging gel bodies 50 are formed by molding to cover thelight-emitting chip 30 and the sensing chip 40 respectively. The twopackaging gel bodies 50 are separated from each other, and a groove 51is provided therebetween. The top surface of each of the packaging gelbodies 50 has a lens portion 52 and a shoulder portion 54. In thispreferred embodiment, for the top surface of each of the packaging gelbodies 50, the shoulder portion 54 surrounds the lens portion 52. Thelens portions 52 of the top surfaces of the packaging gel bodies 50 arehemisphere-shaped. In the manufacturing process, the radius of curvatureof the lens portions 52 of the top surfaces of the packaging gel bodies50 can be modified according to requirements. The packaging gel bodies50 are made of a transparent material, such as transparent epoxy resin.

The cap 60 is disposed on the bearing surface 22 and the packaging gelbodies 50 and fastened to the bearing surface 22 and the packaging gelbodies 50 by adhesive 70. The cap 60 is provided with a light-emittinghole 72 and a light-receiving hole 74. The light-emitting hole 72 andthe light-receiving hole 74 are located above the light-emitting chip 30and the sensing chip 40 respectively. Specifically speaking, the cap 60includes a transverse section 76 and a plurality of extended sections 78extended downwardly from the transverse section 76. The transversesection 76 is provided with the light-emitting hole 72 and thelight-receiving hole 74. The transverse section 76 is fastened to theshoulder portions 54 of the top surfaces of the packaging gel bodies 50by the adhesive 70. The lens portions 52 of the top surfaces of thepackaging gel bodies 50 are accommodated in the light-emitting hole 72and the light-receiving hole 74 respectively. The extended sections 78are located at the groove 51 and the peripheries of the packaging gelbodies 50 respectively and fastened to the bearing surface 22 by theadhesive 70.

The cap 60 is made of an opaque material, such as opaque epoxy resin.

FIGS. 4A-4D illustrate the packaging method of the package structure 10of the long-distance sensor according to the first preferred embodimentof the present invention. The packaging method includes the followingsteps.

(a) Provide the substrate 20 and dispose the light-emitting chip 30 andthe sensing chip 40 on the bearing surface 22 of the substrate 20 in away that the light-emitting chip 30 and the sensing chip 40 areseparated from each other.

(b) Cover the light-emitting chip 30 and the sensing chip 40 by twopackaging gel bodies 50 respectively and separate the packaging gelbodies 50 from each other. It should be mentioned that the two packaginggel bodies 50 in this preferred embodiment are formed by molding tocover the light-emitting chip 30 and the sensing chip 40 respectively,and the packaging gel bodies 50 are separated from each other by directmolding. Besides, in this step when the packaging gel bodies 50 areformed, each of the packaging gel bodies 50 may be formed with a topsurface having a lens portion 52 and a shoulder portion 54.

(c) Dispose a preformed cap 60 on the bearing surface 22 of thesubstrate 20 and the packaging gel bodies 50 and fasten the cap 60 tothe bearing surface 22 of the substrate 20 and the packaging gel bodies50 by adhesive 70. Specifically speaking, in this step the adhesive 70,such as opaque epoxy resin, may be applied to the bearing surface 22 ofthe substrate 20 and the shoulder portions 54 of the top surfaces of thepackaging gel bodies 50 by dispensing, then the cap 60 is disposed onthe bearing surface 22 of the substrate 20 and the packaging gel bodies50, and then the cap 60 is fastened to the bearing surface 22 of thesubstrate 20 and the shoulder portions 54 of the top surfaces of thepackaging gel bodies 54 by baking.

FIGS. 5A-5E illustrate the packaging method of the package structure 10′of the long-distance sensor according to a second preferred embodimentof the present invention. It should be mentioned that the step (a) ofthe second preferred embodiment is the same with the step (a) of thefirst preferred embodiment. The two embodiments are different in that inthe step (b) of the second preferred embodiment a single packaging gelbody 55 is formed by molding to cover the light-emitting chip 30 and thesensing chip 40, and at the same time the aforesaid single packaging gelbody 55 is formed with a top surface having two lens portions 52 whichare located above the light-emitting chip 30 and the sensing chip 40respectively. Then, the aforesaid single packaging gel body 55 is cutinto two packaging gel bodies 50′ separated from each other, wherein thepackaging gel bodies 50′ cover the light-emitting chip 30 and thesensing chip 40 respectively.

After that, in the step (c) of the second preferred embodiment theadhesive 70, such as tin paste, is applied to the bottom of the cap 60by screen printing. At the same time, the shoulder portions 54 of thetop surfaces of the packaging gel bodies 50′ and the position betweenthe packaging gel bodies 50′ are applied with the adhesive 70, such asopaque epoxy resin, by dispensing. After that, the cap 60 is disposed onthe bearing surface 22 of the substrate 20 and the packaging gel bodies50′, and then the cap 60 is fastened to the bearing surface 22 of thesubstrate 20 and the shoulder portions 54 of the top surfaces of thepackaging gel bodies 50′ by baking.

Through the aforesaid steps, the package structure 10′ of thelong-distance sensor as shown in FIG. 3 is manufactured by the packagingmethod of the second preferred embodiment.

In summary of the above description, the cap 60 is fastened to thebearing surface 22 and the packaging gel bodies 50, 50′ by the adhesive70, so that the connection between the materials of the packagestructure 10, 10′ is improved. Besides, the cap 60 is preformed,therefore when the cap 60 is manufactured, the light-emitting hole 72and the light-receiving hole 74 can be provided with specific size forbeing located near the lens portions 52. Then, the cap 60 is directlyfastened to the bearing surface 22 and the packaging gel bodies 50, 50′by the adhesive 70. Because the light-emitting hole 72 and thelight-receiving hole 74 can be located near the lens portions 52, thesensing distance of the long-distance sensor can be increased.

At last, it should be mentioned again that the components disclosed inthe above embodiments of the present invention are instanced forillustration only, not for limiting the scope of the invention. It willbe obvious that the same may be varied and modified in many ways. Suchvariations and modifications are intended to be included within thescope of the following claims.

What is claimed is:
 1. A packaging method of a long-distance sensor, thepackaging method comprising the steps of: (a) providing a substrate anddisposing a light-emitting chip and a sensing chip on a bearing surfaceof the substrate in a way that the light-emitting chip and the sensingchip are separated from each other; (b) covering the light-emitting chipand the sensing chip by two packaging gel bodies respectively andseparating the packaging gel bodies from each other; and (c) disposing apreformed cap on the bearing surface of the substrate and the packaginggel bodies and fastening the cap to the bearing surface of the substrateand the packaging gel bodies by adhesive; wherein in the step (b) whenthe packaging gel bodies are formed, each of the packaging gel bodies isformed with a top surface having a lens portion and a shoulder portion;wherein in the step (c) the adhesive is applied to the bearing surfaceof the substrate and the shoulder portions of the top surfaces of thepackaging gel bodies by dispensing, then the cap is disposed on thebearing surface of the substrate and the packaging gel bodies, and thenthe cap is fastened to the bearing surface of the substrate and theshoulder portions of the top surfaces of the packaging gel bodies bybaking.
 2. The packaging method as claimed in claim 1, wherein in thestep (b) the two packaging gel bodies are formed by molding to cover thelight-emitting chip and the sensing chip respectively.
 3. The packagingmethod as claimed in claim 1, wherein in the step (b) the packaging gelbodies are separated from each other by cutting or direct molding.
 4. Apackaging method of a long-distance sensor, the packaging methodcomprising the steps of: (a) providing a substrate and disposing alight-emitting chip and a sensing chip on a bearing surface of thesubstrate in a way that the light-emitting chip and the sensing chip areseparated from each other; (b) covering the light-emitting chip and thesensing chip by two packaging gel bodies respectively and separating thepackaging gel bodies from each other; and (c) disposing a preformed capon the bearing surface of the substrate and the packaging gel bodies andfastening the cap to the bearing surface of the substrate and thepackaging gel bodies by adhesive; wherein in the step (b) when thepackaging gel bodies are formed, each of the packaging gel bodies isformed with a top surface having a lens portion and a shoulder portion;wherein in the step (c) the adhesive is applied to a bottom of the capby screen printing and applied to the shoulder portions of the topsurfaces of the packaging gel bodies and a position between thepackaging gel bodies by dispensing, then the cap is disposed on thebearing surface of the substrate and the packaging gel bodies, and thenthe cap is fastened to the bearing surface of the substrate and theshoulder portions of the top surfaces of the packaging gel bodies bybaking.
 5. The packaging method as claimed in claim 4, wherein in thestep (b) the two packaging gel bodies are formed by molding to cover thelight-emitting chip and the sensing chip respectively.
 6. The packagingmethod as claimed in claim 4, wherein in the step (b) the packaging gelbodies are separated from each other by cutting or direct molding.